word - South Pacific Regional Fisheries Management Organisation

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Information describing black cardinalfish (Epigonus telescopus)
fisheries relating to the South Pacific Regional Fisheries
Management Organisation
WORKING DRAFT
21 June 2007
1
2
Overview .................................................................................................................... 2
Taxonomy .................................................................................................................. 3
2.1
Phylum ................................................................................................................ 3
2.2
Class .................................................................................................................... 3
2.3
Order ................................................................................................................... 3
2.4
Family ................................................................................................................. 3
2.5
Genus and species ............................................................................................... 3
2.6
Scientific synonyms ............................................................................................ 3
2.7
Common names .................................................................................................. 3
2.8
Molecular (DNA or biochemical) bar coding ..................................................... 3
3
Species Characteristics ............................................................................................. 3
3.1
Global distribution and depth range .................................................................... 3
3.2
Distribution within South Pacific area ................................................................ 4
3.2.1
Inter-annual and/or seasonal variations in distribution ............................... 4
3.2.2
Other potential areas where the species may be found ............................... 4
3.3
General habitat .................................................................................................... 4
3.4
Biological characteristics .................................................................................... 4
3.5
Population structure ............................................................................................ 5
3.6
Biological productivity ....................................................................................... 6
3.7
Role of the species in the ecosystem................................................................... 6
4
Fisheries Characterisation ....................................................................................... 6
4.1
Distribution of fishing activity ............................................................................ 6
4.2
Fishing technology .............................................................................................. 6
4.3
Catch history ....................................................................................................... 6
4.4
Status of stocks ................................................................................................... 6
4.5
Threats................................................................................................................. 6
4.6
Fishery value ....................................................................................................... 7
5
Current Fishery Status and Trends ........................................................................ 7
5.1
Stock size ............................................................................................................ 7
5.2
Estimates of relevant biological reference points ............................................... 7
5.2.1
Fishing mortality ......................................................................................... 7
5.2.2
Biomass ....................................................................................................... 7
5.2.3
Other relevant biological reference points .................................................. 7
6
Impacts of Fishing ..................................................................................................... 8
6.1
Incidental catch of associated and dependent species......................................... 8
6.2
Unobserved mortality of associated and dependent species ............................... 8
6.3
Bycatch of commercial species ........................................................................... 8
6.4
Habitat damage ................................................................................................... 8
7
Management .............................................................................................................. 9
7.1
Existing management measures inside EEZs ..................................................... 9
7.2
Existing management measures in areas beyond national jurisdiction ............... 9
7.3
Fishery management implications ...................................................................... 9
7.3
Ecosystem considerations ................................................................................... 9
8
Research ..................................................................................................................... 9
8.1
Current and ongoing research ............................................................................. 9
8.2
Research needs .................................................................................................... 9
9
Additional Remarks ................................................................................................ 10
10
References ............................................................................................................ 10
WORKING DRAFT
1
Overview
Black cardinalfish (Epigonus telescopus) are widely distributed in the North
Atlantic and South Atlantic, Indian, and Southwest Pacific Oceans.
They are found at depths of 75–1200 m and caught mainly by deepwater bottom
trawl as bycatch of fisheries targeting alfonsino or orange roughy.
Unvalidated otolith readings from the South Pacific indicate that black
cardinalfish is relatively slow-growing and long lived. The juveniles are pelagic
and undergo major ontogenetic changes. Little is known of adult movements.
Reproductive biology is not well known. There is no information on black
cardinalfish stock structure as data is lacking on genetics, distribution of
spawners, and adult movements.
Black cardinalfish are typically by-catch of fisheries targeting alfonsino (Beryx
splendens) (characteristically >400 m) or orange roughy (typically about 800 m).
Since 1992 large catches of black cardinalfish have been taken on the high seas on
the Northern Challenger Plateau and the southern Lord Howe Rise.
The main method used to catch black cardinalfish is a high-opening trawl
generally fished hard down on the bottom. Trawling for this species on seamounts
impacts habitat, but the precise impact of this on the black cardinalfish
populations or other species on the seamounts is unknown.
Black cardinalfish is a deepwater species with limited habitat in the high seas area
of the South Pacific and assumed low resilience to fishing pressure. Given their
longevity and late maturation the biological productivity of black cardinalfish is
likely to be low.
There are currently no known management measures in place for black
cardinalfish.
This is a living document. It is a draft report and requires additional information
to complete.
2
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2
Taxonomy
2.1
Phylum
Vertebrata
2.2
Class
Actinopterygii
2.3
Order
Perciformes
2.4
Family
Epigonidae
2.5
Genus and species
Epigonus telescopus (Risso, 1810)
2.6
Scientific synonyms
None known
2.7
Common names
Black cardinalfish
2.8
Molecular (DNA or biochemical) bar coding
No information
3
Species Characteristics
3.1
Global distribution and depth range
Black cardinalfish are widely distributed in the North Atlantic from Iceland to the
Canary Islands, in the western Mediterranean, and in the South Atlantic, Indian,
and Southwest Pacific Oceans (Abramov 1992).
Black cardinalfish are found from 75–1200, but their preferred depth range is
600–900 m (Field et al. 1997). The preferred depth range of schools (600-900 m)
overlaps the upper end of the depth range of orange roughy (Hoplostethus
atlanticus) and the lower end of alfonsino (Beryx splendens) and bluenose
(Hyperoglyphe antarctica).
3
3.2
WORKING DRAFT
Distribution within South Pacific area
In the Southwest Pacific, black cardinalfish are found between Australia and New
Zealand (Abramov 1992) (see Figure 1).
Figure 1: Known distribution of black cardinalfish on the high seas in the South Pacific Ocean.
3.2.1
Inter-annual and/or seasonal variations in distribution
No information
3.2.2
Other potential areas where the species may be found
No information
3.3
General habitat
Black cardinalfish are bathy-demersal. Adults are benthic or bentho-pelagic on
continental slopes where they are found mostly in mobile schools up to 150 m of
the bottom over hills and rough ground. The juveniles are pelagic.
3.4
Biological characteristics
Slow growing up to 75 cm (~104 years). The average size of black cardinalfish
landed by the commercial fishery is about 50–60 cm fork length (FL) (Annala et
al. 2004). Length frequency distributions from research surveys are unimodal with
a peak at 55–65 cm FL. Unvalidated otolith readings from over 700 fish from
eastern New Zealand waters indicate that this species is relatively slow-growing
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WORKING DRAFT
and long lived. Maximum ages of over 100 years were reported, with the bulk of
the commercial catch being between 35 and 55 years of age.
However, Pshenichny et al. (1986) (as cited in Abramov 1991), examined whole
otoliths and considered that black cardinalfish on the North Atlantic Ridge
attained a length of about 70 cm at only 10 years. Pshenichny et al. (1986) (as
cited in Vinnichenko 1997), stated that black cardinalfish become sexually mature
at age 7. These age estimates are well below Tracey et. al.’s assumed estimates of
age at full recruitment and maximum ages. However Pshenichny et al. (1986) also
reported lengths at maturity as 40-50 cm, similar to Tracey et al’s estimate of full
age at recruitment of 45 years.
The juveniles are pelagic and undergo major ontogenetic changes (Mauge &
Mayer 1990). Little is known of adult movements. Reproductive biology is not
well known. From research surveys and Observer Programme data in New
Zealand, spawning may occur in early winter (Field et al. 1997). Northern species
of cardinal fish also appear to spawn in autumn/early winter (March–May)
(Mauge & Mayer 1990).
Life history parameters are given below (Tracey et al. 2000):
Parameter
Natural mortality
Age at recruitment
Age at maturity
Gradual recruitment
Gradual maturity
Von Bertalanffy parameters
Length-weight parameters
Recruitment variability
Recruitment steepness
Symbol
M
Ar
As
Sr
Sm
Linf
K
t0
a
b
σR
All
0.034
45
45
13
13
70.8
0.034
-6.32
0.027
2.87
1.2
0.75
Male
–
–
–
–
–
70.9
0.038
-4.62
–
–
–
–
Female
–
–
–
–
–
67.8
0.034
-8.39
–
–
–
–
Morphological characteristics
E. telescopus have dorsal spines (total) 7-8; dorsal soft rays (total) 9-11; anal
spines 2; anal soft rays 9. No opercular spines. 8 spines on first dorsal fin. Snout
blunt, eye large, mouth large, lower jaw equalling or slightly protruding beyond
upper jaw. Pyloric caeca 21-34. Brown-violet or black, iridescent in life.
3.5
Population structure
There is no information on stock structure as data is lacking on genetics,
distribution of spawners, and adult movements.
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3.6
Biological productivity
This is a slow growing and long-lived species with late maturation. The bulk of
the commercial catch is between 35 and 55 years of age. Accordingly, black
cardinalfish are relatively susceptible to growth overfishing and population
depletion.
3.7
Role of the species in the ecosystem
Black cardinalfish are assumed to be carnivorous, feeding on small fishes and
planktonic invertebrates. Prey items observed from research surveys in New
Zealand waters include mesopelagic fish, natant decapod prawns, and octopus
(Clark & King, 1989).
4
Fisheries Characterisation
4.1
Distribution of fishing activity
E. telescopus are typically bycatch of fisheries targeting alfonsino (Beryx
splendens) (characteristically >400 m) or orange roughy (typically about 800 m).
Other commonly caught commercial species are boarfish (Pseudopentaceros
richardsoni) and bluenose (Hyperoglyphe antarctica) (Ministry of Fisheries and
Marine Resources 2001).
Since 1992 the largest known catches on the high seas in the South Pacific have
been taken on the Northern Challenger Plateau and the southern Lord Howe Rise
(Field et al. 1997).
4.2
Fishing technology
Black cardinalfish are taken by deepwater bottom trawl.
4.3
Catch history
Around half the New Zealand catch (Table 1, Ministry of Fisheries 2007) has
been taken as bycatch, with 80% taken in the orange roughy fisheries. Australian
vessels have reported landings of 78 tonnes in the period 1987-2006 (Sampaklis
et. al. 2007).
4.4
Status of stocks
The stock status is not known or uncertain, but it is assumed that it is at least
moderately exploited. Some specific areas maybe more exploited than others.
4.5
Threats
No threat status known.
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Table 1: Reported estimated catches (t) taken outside EEZs in the South Pacific region by
New Zealand vessels. These figures do not include catches by vessels of other nations. 1990 =
estimated catches 1 October 1990–30 September 1991 (NZ Ministry of Fisheries 2007)
Year
Epigonus
telescopus
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
Total
4.6
11
10
245
1,058
320
265
351
182
325
151
485
159
227
87
188
21
4,081
Fishery value
Section yet to be developed
5
Current Fishery Status and Trends
5.1
Stock size
There are no known estimates of stock size in the South Pacific.
5.2
Estimates of relevant biological reference points
5.2.1
Fishing mortality
No information
5.2.2
Biomass
No information
5.2.3
Other relevant biological reference points
No information
7
WORKING DRAFT
6
Impacts of Fishing
6.1
Incidental catch of associated and dependent species
No estimates available.
6.2
Unobserved mortality of associated and dependent species
No estimates available.
6.3
Bycatch of commercial species
Whilst targeting black cardinalfish, on the high seas in the South Pacific region,
New Zealand flagged vessels have reported over 100 tonnes of alfonsino and over
5 tonnes each of black oreo, orange roughy and spiky oreos as bycatch between
the years 1993- 2006.
6.4
Habitat damage
The main method used to catch this species is a high-opening trawl generally
fished hard down on the bottom. Trawling for this species on seamounts impacts
habitat (Clark and O’Driscoll 2003; Koslow et al. 2001), but the precise impact of
this on the black cardinalfish populations or other species on the seamounts is
unknown.
Studies have shown that repeated trawl disturbances alter the benthic community
by damaging or removing macro-fauna and encouraging anaerobic bacterial
growth (see review by Cryer et al. (in prep). Severe damage of coral cover from
bottom trawl fishing inside the Australian EEZ has been documented (Koslow et
al. 2001). Video images reveal bare rock and pulverized coral rubble where
bottom trawling has occurred.
Bottom trawling also tends to homogenise the sediment, which damages the
habitat for certain fauna. Benthic processes, such as the transfer of nutrients,
remineralisation, oxygenation and productivity, which occur in undisturbed,
healthy sediments, are also impaired (Cryer et al. in prep).
As fishing gear disturbs soft sediment they produce sediment plumes and remobilise previously buried organic and inorganic matter. This increase in the rates
of nutrients into the water column has important consequences for the rates of
biogeochemical cycling (Kaiser et al. 2002).
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WORKING DRAFT
7
Management
7.1
Existing management measures inside EEZs
Landings of black cardinalfish in the New Zealand and Australian EEZs are
regulated by quotas.
7.2
Existing management measures in areas beyond national jurisdiction
There are currently no regulations in place for black cardinalfish on the high seas.
7.3
Fishery management implications
The lack of information, especially a direct stock assessment, exacerbates risk.
The unknown status of the population and very low productivity of this species,
and the general lack of information render this species vulnerable to overfishing.
Black cardinalfish is a deepwater species with limited habitat and low resilience.
7.3
Ecosystem considerations
The main method used to catch this species is a high-opening trawl generally
fished close to, or on, the bottom. Trawling for this species on seamounts—which
has taken place—will bring about habitat change, but the precise impact of this on
the alfonsino populations and other species on the seamount is unknown.
8
Research
8.1
Current and ongoing research
Within EEZs
In specific quota management areas inside New Zealand’s EEZ length and age
information have been collected (Tracey et al. 2000).
High seas
None known
8.2
Research needs
To date the ageing technique using marginal increment analysis of adult black
cardinalfish otoliths has not been validated. This validation remains a high
priority for this species. Information on biomass and other relevant biological
parameters is also needed. Sampling of length frequency data to determine the
size composition of commercial catches is necessary for black cardinalfish caught
outside EEZs in the South Pacific.
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9
Additional Remarks
High levels of mercury (Hg) have been reported in a sample of black cardinalfish
from the Bay of Plenty, New Zealand. The mean mercury level (1.47 mg.kg-1)
was well above the maximum permissible level of 0.5 mg.kg-1 set by the New
Zealand Department of Health (Tracey, 1993).
The genus Epigonus consists of 12 species, the most closely related being E.
angustifrons, E. notacanthus, and E. macrops. All lack opercular spines and have
8 spines in the first dorsal and a larger number of pyloric caeca (Abramov 1992).
One species, called Besugo Epigonus crassicaudus is endemic to Chile. They are
found at depths of 100–550 m and caught between Valparaiso (33°30’S) and
Puerto Montt (42°S) by trawling typically as bycatch of fisheries targeting
common hake or Patagonian grenadier. This species may occur on the Nazca
Ridge.
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References
Abramov, A. (1991). Age and growth of two species of bigeyes, Epigonus
angustifrons and E. elegans, from the Indian and Pacific Oceans. Journal of
Icthyology 31: 125-131.
Abramov, A. (1992). Species composition and distribution of Epigonus
(Epigonidae) in the world ocean. Journal of Ichthyology 32: 17–31.
Annala, H.; Sullivan, K.J.; Smith, N.M.W.M.; Griffiths, M.H.; Todd, P.R.; Mace,
P.M.; Connell, A.M. (2004). Report from the Fishery Assessment Plenary, May
2004: stock assessments and yield estimates.
Clark, M.R.; King, K.J.; McMillan, P.J. (1989). The food and feeding
relationships of black oreo, Allocyttus niger, smooth oreo, Pseudocyttus
maculatus, and eight other fish species from the continental slope of the southwest Chatham Rise, New Zealand. Journal of Fish Biology 35: 465–484.
Clark, M.; O'Driscoll, R. 2003: Deepwater fisheries and aspects of their impact on
seamount habitat in New Zealand. Journal of Northwest Atlantic Fishery Science
31: 441-458
Cryer, M., Nodder, S., Thrush, S., Lohrer, D., Gorman, R., Vopel, K., Baird, S.
(unpublished). The effects of trawling and dredging on bentho-pelagic coupling
process in the New Zealand EEZ. New Zealand Aquatic Environment and Marine
Biodiversity Report 2005/ ?. 66p.
Field, K.D.; Tracey, D.M.; Clark, M.R. (1997). A summary of information on,
and assessment of the fishery for, black cardinalfish, Epigonus telescopus (Risso,
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WORKING DRAFT
1810) (Percoidei: Apogonidae). New Zealand Fisheries Assessment Report
1997/97/22. 5 p.
Kaiser, MJ., Collie, JS., Hall, SJ., Jennings, S., Poiner, IR. (2002). Modification
of marine habitats by trawling activities: prognosis and solutions. Fish and
Fisheries 3:114-136
Koslow, J.A.; Gowlett-Holmes, K.; Lowry, J.K.; O’Hara, T.; Poore, G.C.B.; and
Williams, A. (2001). Seamount benthic macrofauna off southern Tasmania:
community structure and impacts of trawling. Marine Ecology Progress Series
213: 111-125.
Mauge, L.A., Mayer, G.F. (1990). Apogonidae. In Quero, JC. (eds.) Check-list of
the fishes of the eastern tropical Atlantic. JNICT, Lisbon; SEI Paris; UNESCO,
Paris vol. 2, 714-718.
Ministry of Fisheries and Marine Resources (2001). Report of the Ad Hoc
Meeting on Management of Deepwater Fisheries Resources of the Southern
Indian Ocean. Swakopmund, Namibia, 30 May - 1 June 2001. FAO Fisheries
Reports 652. 61 p.
New Zealand Ministry of Fisheries. 2007. New Zealand fisheries for non-highly
migratory fish in the indicative organisation area of the proposed South Pacific
regional fisheries management organization: 1990 – 2006. Working Paper
presented at the SPRFMO Data and Information Working Group meeting and
Science Working Group meeting, Chile April, 2007.
Sampaklis, A. J., Morison, A. K., and P.I. Hobsbawn. 2007. Australian fishing for
non-highly migratory fish (1987 – 2006) in the area of the proposed South Pacific
regional fisheries management organisation. Working Paper presented at the
SPRFMO Data and Information Working Group meeting, Chile April, 2007.
Tracey, D.M.; George, K.; Gilbert, D.J. (2000). Estimation of age, growth, and
mortality parameters of black cardinalfish (Epigonus telescopus) in QMA 2 (east
coast North Island). New Zealand Fisheries Assessment Report 2000/27. 21 p.
Vinnichenko, V.I. (1997). Russian investigations and deepwater fishery on the
Corner Rising seamount in Subarea 6. Sci. Counc. Stud. NAFO. pp. 41-49.
http://www.fao.org
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